mannesman



2 Sheets-Sheet 1 (Modem M. MANNESMANN.

MANUPAGTURE 0F SEAMLESS TUBES.

Patented Apr. 26, 1887.

(Model.) 2 Sheets-Sheet 2. M. MANNESMANN.

MANUPAGTURB 01.-" SEAMLBSS TUBES.

Patented Apr. 26, 1887.

UNITED STATES PATENT OFFICE.

MAX MANNESMANN, OF REMSCHEID, (vfERll'IANY.V

MANUFACTURE OF SEAMLESS TUBES.

SPECIFICATION forming pari'. of Letters Patent No. 361,961, dated April26, 1887. Application tiled April 1. i857. Serial No. 233,246. (Model.)Patented in Belgium August 14, 1836, No. 54,857.

To all whom it may concern.-

Be it known that I, MAX MANNEsMANN, of Remscheid, Germany, have inventedcertain Improvements in the Manufacture of Seamless Tubing from SolidIngots of Metal, of which the following is a specification.

This invention relates to a modification of the process of forming tubesfrom solid ingots or blanks solely by means of diagonally-actingreducing-rolls, between the converging working-faces of which suchingots or blanks are passed endwise, and by the action of which thetubular formation is initiated by the rupturing of the ingots or blanksalong the line of their longitudinal axes; and the present inventionconsists in the co mbination,with properly p roportioned and adjusteddiagonally-acting rolls, of a mandrel or plug which is so placed as toenter the hole produced in the blank by the action of the rolls, butwhich does not touch the solid central portion of the blank, or, inother words, does not bear upon the part of the blank where the tubularformation is initiated, contact with which, in the case of a steelblank, owing to its highly-heated condition, would soon destroy the endof the mandrel. The mandrel in this combination is used especially forthe purpose of serving as a plug for preventing the free access of airto and consequent oxidation of the interior of the part of the blankwhich is in process of transformation into a tube, and incidentally asan anvil upon which the shell of the tube is progressively compressed bythe final action of the external rolls, whereby the interior surface ofthe tube is rendered smooth, and, ow-

ing to the absence of oxidation, any cracks or breaks therein aregenerally closed up land welded.

The mandrel may be combined with rolls which impart a twist to the shellof the tube, or with rolls which develop the tubular formation withoutimparting such twist.

As apparatus for rolling tubes by means of diagonally-acting rolls iswell known, it is not deemed necessary to show or describe herein anyorganized machine, or anything more than the relative arrangement of themandrel 4and diagonally-acting rolls by which they are made to have themode of combination and operation which is eomprehended in the presentinvention.

The drawings are as follows: Figure l is a side elevation of a pair ofdiagonally-acting cylindre-conoidal rolls, arranged one above and onebelow the axial' line of a conical mandrel, showing, in centrallongitudinal section, a solid metallic blank which has commenced itspassage between the converging opposed working-surfaces of the rolls,and by the pinching action to which it has been subjected has had itsdiameter slightly reduced and a shallow cavity formed in its forwardend. Fig. 2 is a similar view of the rolls and mandrel, showing theblank at a further stage of its progressv between the rolls, in which ithas progressed so far that the pointed end of the mandrel has enteredwithin the `cavity in the forward end of the blank. Fig. 3 is a similarelevation of the rolls and mandrel, in which the blank is represented ashaving acquired the tubular form and as so far progressed between therolls that its rear end has nearly reached the pointed end of themandrel 5 and Fig. 4 is an end elevation of the rolls and mandrel,representing the mandrel shaft and tube in transverse section on thedotted linea: x in Fig. 3. Fig. 5 is a representation of a mandrel andof two pairs of diagonally-acting rolls, one pair for transforming asolid blank into a tube and the other pair for compressing the shell ofsuch tube upon the surface of a cylindro-conoidal mandrel. Fig. 6 is atop view illustrating the combination of a conical mandrel with a pairof diagonally-acting disk` rolls respectively mounted upon the opposedends of convergent shafts, and showing in central longitudinal section ablank in process of transformation into a tube by its passage betweenthe convergent working-faces of the disks. Fig. 7 is an end elevation ofthe diskrolls show'n in Fig. 6, which are herein illustrated merelybecause they maybe used as substitutes for the diagonally-actingcylindreconoidal rolls shown in Fig. 1.

The employment of diagonally-acting rolls for transforming into a tube asolid metallic blank which is passed endwise between the convergingopposed faces of the rolls is fully described in another pendingapplication, and therefore the mode of proportionment and the mode ofadj ustment by which diagonally-acting rolls are made capable ofperforming this function do not of themselves constitute a part IOO ofthe present invention, which, so far as it comprehends the apparatusemployed,is limited to acombination of such rolls with amandrel orplngwhich enters into the tube formed by the action of the rolls, butwhich does not touch the solid central portion of the blank. Theinvention is not limited to the employment of any particular form ofrolls, but is present in any ease when diagonally-acting rolls soproportioned and adjusted as to transform a solid blank into a tube bythe impingement of opposed portions of their workingsurfaces upon theexterior of the blank are combined with a mandrel or plug in the mannerherein set forth.

Referring to the drawings, the cylindro-eonoidal rolls A a (shown inFig. l) are mounted upon horizontal shafts A a', the vertical planes ofwhich intersect at the same angle, but in opposite directions, thevertical plane of the mandrel B. Preferably the cylindrical portion b ofthe mandrel occupies the space midway between the cylindrical portionsA2 a2 of the diagonal rolls, and the tapering portion b of the mandrelprojects into the space between the conoidal portions A3 a3 of therolls. At its base the mandrel is stepped or soeketed `in the shaft B',the opposite end of which is stepped or soeketed in the standard C, orin some other stationary part of the machine.

The solid blank D is fed into the wider end of the space between therolls. The immediate effect produced upon the forward end of the blankby the impingement upon it of the working-faces of the rolls is areduction in diameter and the formation of the cavity d in the forwardend of the blank, as illustrated in Fig. 1. As the blank progresses, thecavity d in its forward end becomes deeper, as illustrated in Fig. 2. Bythe forward progress of the blank, the end of the conical mandrel isentered into the cavity d, and finally the metallic blank is compressedupon the surface of the mandrel, and issues from the narrow end of thespace between the rolls in the form of a tube, d, as illustrated in Fig.3. The tubular formation is, however, so far developed in the blank bythe preliminary action of the rolls that the pointed end of the mandrelneed not acquire contact with the solid central portion of the blank.During its passage between the rolls the blank may be guided by means ofthe lateral guides E e, affixed, respectively, to the standards E e', orother stationary parts of the machine, as illustrated in Fig. 4.

Fig. 5 illustrates a modieation of the apparatus, in which twodiagonally-acting rolls, F f, are employed to transform a solid blankinto a tube, and the adjoining pair of diagonally-actin g rolls, G g,are respectively arranged on opposite sides of the eylindro-conoidalmandrel B, for the purpose of receiving the tube formed by the rolls F fand compressing, -reducing the thickness, and welding the interiorsurface of the shell of such tube, and thereby transforming it into thefinished tube (Z, as shown.

It will of course be understood that in the operation of compressing theshellof the tube upon the mandrel the exterior diameter of the tube maybe simultaneously reduced without changing the interior diameter, or theinterior diameter may be enlarged without changing the exteriordiameter, or the exterior diameter may be reduced and the interiordiameter at the .same time enlarged; and it will also be seen that themandrel need not necessarily be pointed and need not necessarily becylindrical for any considerable part of its length, and that it mayhave any portion of its surface curved in the direction of its length,either conveXly or concavely.

What is claimed as the invention isl. The improvement in the art oftrans forming a solid metallic ingot or blank into an interiorly smoothand compressed seamless tube, which consists in progressively reducingthe blank in diameter and rupturing it along the line of its axis, andconcurrently causing the metal to move from the center out-` wardly bymeans of external rolls respectively impinging upon different sides ofthe blank, and in then smoothing and compressing the interior of saidtube, either in thesame or in another machine,by means of a mandrel orplug introduced into the said tube and between the working-faces ofdiagonally-acting rolls for a sufficient distance to serve as an anvilupon which the shell ofthe tube is progressively compressed by theimpingement upon it ofthe diagonally-acting rolls.

2. In apparatus for transforming solid metallic ingots or blanks intotubes, two or more diagonally-acting reducing-rolls suitablyproportioned and adjusted relatively to the blank which is to beoperated upon for effecting the rupture of the blank along the line ofits axis, and for concurrently causing the metal thereof to move fromthe center outwardly, in combination with a mandrel or plug interposedbetween portions of the working-faces of the rolls for the purpose ofpreventing the free access of air to and the consequent oxidation of theinterior of the portion of the blank which is in process oftransformation into a tube, and for serving as an anvil upon which theshell of the tube is progressively compressed, whereby any cracks orcavities in its interiorsurface are closed up or welded.

3. In apparatus for transi'brming solid metallic ingots or blanks intotubes, two or more diagonally-acting reducing-rolls suitablyproportioned and adjusted relatively to the blank which is to beoperated upon for effecting the rupture of the blank along the line ofits axis, and for eoncurrentl y causing the, metal thereof to move fromthe center outwardly, in combination with two or more adjoiningdiagonallyacting rolls and a mandrel or plug introduced between theworking-faces of the said adjoining rolls, as and for the purposes setforth.

Vitnesses: MAX MANNESMANN.

A. M. JoNns, M. L. ADAMs.

IOO

